<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <!-- 用form来构造一个post请求,把用户名和密码通过body键值对的形式传过去，此处login为相对路径 -->
    <form action="login" method="post">
        <input type="text" name="username">
        <input type="password" name="password">
        <input type="submit" name="提交">
    </form>
</body>
</html>